Abstract: The aim of the present study was to assess the effects of cinnamic acid and citric acid mixture supplementation on laying performance of hens during the peak period, and to evaluate the application value of the mixture as an alternative for antibiotics in livestock and poultry production. A total of 1000 24-week-old Hy-Line Brown Laying Hens were randomly assigned to 4 mixture-treated groups（30, 60, 120, 240 mg/kg） and one basal diet control group. The whole experiment lasted for 28 days during which the health status of the laying hens was observed and their productive performance was determined. The results showed that the diarrhea incidence and morbidity in 30 mg/kg group were significantly lower than those of the control group（P〈0.05）, but the diarrhea incidence was increased as the higher dosages of the mixture was added. Compared to the control group, the significantly increased feed conversion rate（FCR） was observed in both 30 mg/kg and 60 mg/kg groups（P〈0.05）. In conclusion, dietary supplementation of 30-60 mg/kg of cinnamic acid and citric acid mixture during the peak period is able to improve the productive performance of laying hens and to decrease the diarrhea incidence and morbidity.